"When I joined Tesco, somebody said to me, 'They’ll eat you alive,' because it was known as a bit of a hard-charging place. That sort of brought out the street kid in me, and made me a little bit hard and combative. I had to learn later that there’s another way to get the best out of people, which is to really motivate them and make them feel good about themselves. So I changed. If I had to sum it up...[be] generous at work rather than selfish."

Leahy's golden rule: treat your co-workers the way you’d like to be treated. He believes that being kind to others can build trust among team members and strengthen relationships within a company. Bringing people down to make yourself look good may seem like a short cut to the top, but in the long run, burning bridges won't get you anywhere. You want to avoid being resented by your co-workers in the future. It's healthier for you, and for your company, to be kind to others while you climb the corporate ladder.

"For some people, that’s a transition that they have to make, and not everybody can make it. Sometimes the brightest find it the hardest to make that transition because they’ve always been better than the people around them...It also has a lot to do with making people feel good about themselves. Bureaucracy will tend to lower self-esteem, so if you consciously build people up so that they say, 'I matter here and people respect me and they think I can contribute and they trust me to contribute,' that really gets the best out of people."

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